Scanned display with dual signal fiber transmission

• US 6,151,167 A
• Filed: 08/05/1998
• Issued: 11/21/2000
• Est. Priority Date: 08/05/1998
• Status: Expired due to Term

• Current Assignee: Microvision, Inc.
• Original Assignee: Microvision, Inc.
• Inventors: Melville, Charles D.
• Primary Examiner(s): Dang, Hung Xuan
• Application Number:
  US09/128,955
• Time in Patent Office: 839 Days
• Field of Search: 359/204, 359/202, 359/201, 359/618, 359/629, 385/88
• US Class Current: 359/618
• CPC Class Codes: G02B 27/017 Head mounted
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 5/30 Polarising elements light-modulating devices with active elements G02F1/00
• CPC Class Codes: G06F 3/013 Eye tracking input arrangements G06F3/015 takes precedence

Abstract

A scanning display includes a control unit and a scanning head linked by a tether. The control unit outputs two beams of orthogonally polarized light, each beam being modulated with a respective set of image information. The fiber is a polarization-maintaining fiber that receives the orthogonally polarized beams and carries them to the scanning head. At the scanning head, a birefringent material separates the beams spatially in response to their different polarizations. Vertical and horizontal scanners then scan the separated beams through a substantially raster pattern to produce an image.

Claims

1. A display apparatus for displaying an image, comprising:

a light source operative to produce first and second beams, each of the first and second beams being modulated according to a portion of the image, the second beam having a polarization shifted from the first beam by a selected polarization shift;

a polarization maintaining optical fiber having an input end and an output end, the input end being coupled to receive both of the first and second beams simultaneously from the light source, the polarization maintaining fiber being constructed to maintain the relative polarizations of the first and second beams;

a scanning assembly having a scanner input and a scanner output, the scanner input being coupled to the fiber output to receive the first and second beams, the scanning assembly being configured to construct a virtual image at the scanner output from the received beams; and

beam separating optics in the scanning assembly, the beam separating optics being positioned to receive the combined first and second beams scanned beams, the beam separating optics further being responsive to the polarizations of the first and second beams to direct the first beam along a path different from the second beam.

2. The display apparatus of claim 1 wherein the beam separating optics includes a birefringent material positioned to intercept the combined beams.

3. The display apparatus of claim 1 wherein the scanning assembly includes a horizontal scanner positioned between the second end of the polarization maintaining fiber and the beam separating optics.

4. The display apparatus of claim 1 wherein the scanning assembly includes a horizontal scanner positioned between the beam separating optics and the scanner output.

5. A scanning assembly for a display apparatus, comprising:

a beam input adapted for coupling to a fiber and configured to receive light from a fiber;

beam separating optics positioned to receive light from the beam input, the beam separating optics including a polarization sensitive material operative to redirect portions of the received light along respective paths corresponding to the polarization of the respective portion; and

a scanner aligned to receive the portions of the light, the scanner being configured to redirect the received portions of light through a predetermined scan pattern.

6. The scanning assembly of claim 5 wherein the polarization sensitive material is a birefringent crystal.

7. The scanning assembly of claim 5 wherein the scanner is a mechanically resonant scanner.

8. The scanning assembly of claim 5 wherein the beam separating optics are positioned between the scanner and the beam input.

9. The scanning assembly of claim 5 wherein the scanner is positioned between the beam separating optics and the beam input.